Left common carotid artery
Branch · 2nd arch branch Bifurcates C3/C4
Second arch branch, arising just left of and behind the brachiocephalic trunk, so its thoracic course is longer than the right's. Ascends in the carotid sheath with the internal jugular vein and vagus and bifurcates at the upper border of the thyroid cartilage (C3/C4) into internal and external carotid arteries; it has no branches before this.
Traced from the start
- Arch of the aorta
- Left common carotid artery
Detail
- Level
- Arch (T4/T5) to bifurcation at C3/C4
- Terminal branches
- Internal carotid (brain, eye) and external carotid (face, neck, scalp)
- Relations
- Carotid sinus (baroreceptor) and carotid body (chemoreceptor) at the bifurcation; vagus behind, between artery and internal jugular vein
When it goes wrong
Atheroma at the carotid bifurcation
Embolic transient ischaemic attack or stroke in the ipsilateral middle cerebral territory, amaurosis fugax via the ophthalmic artery; a carotid bruit
Carotid sinus massage or pressure from a tight collar
Baroreceptor-mediated bradycardia and hypotension; carotid sinus hypersensitivity causes syncope
Practise this structure
1 question in the bank tagged Arterial Supply.